From: "Abhishek Rai" Subject: Re: [CALL FOR TESTING] Make Ext3 fsck way faster [2.6.24-rc6 -mm patch] Date: Thu, 24 Jan 2008 08:14:21 -0500 Message-ID: References: <200801230412.16992.abhishekrai@google.com> <20080123234905.35664ed6.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: linux-kernel@vger.kernel.org, linux-ext4@vger.kernel.org, rohitseth@google.com To: "Andrew Morton" Return-path: Received: from smtp-out.google.com ([216.239.33.17]:25495 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754849AbYAXNO3 (ORCPT ); Thu, 24 Jan 2008 08:14:29 -0500 Received: from zps78.corp.google.com (zps78.corp.google.com [172.25.146.78]) by smtp-out.google.com with ESMTP id m0ODELCj000880 for ; Thu, 24 Jan 2008 13:14:22 GMT Received: from rv-out-0910.google.com (rvbk15.prod.google.com [10.140.87.15]) by zps78.corp.google.com with ESMTP id m0ODEI4O016775 for ; Thu, 24 Jan 2008 05:14:21 -0800 Received: by rv-out-0910.google.com with SMTP id k15so214488rvb.2 for ; Thu, 24 Jan 2008 05:14:21 -0800 (PST) In-Reply-To: <20080123234905.35664ed6.akpm@linux-foundation.org> Content-Disposition: inline Sender: linux-ext4-owner@vger.kernel.org List-ID: No, it didn't. I measured read from a 10GB sequentially laid out file with standard benchmarking practices (cold cache, multiple runs, low std. deviation in results, etc.) and here are the results: File created by vanilla Ext3 being read by vanilla Ext3: Total: 3m16.1s User: 0.0.5s Sys: 13.9 File created by mc Ext3 being read by mc Ext3 (with the buffer boundary logic disabled): Total: 3m15.5s User: 0.05s Sys: 13.6s Thanks, Abhishek On Jan 24, 2008 2:49 AM, Andrew Morton wrote: > > On Wed, 23 Jan 2008 04:12:16 -0500 Abhishek Rai wrote: > > > I'm wondering about the interaction between this code and the > > > buffer_boundary() logic. I guess we should disable the buffer_boundary() > > > handling when this code is in effect. Have you reviewed and tested that > > > aspect? > > > > Thanks for pointing this out, I had totally missed this issue in my change. I've now made the call to set_buffer_boundary() in ext3_get_blocks_handle() subject to metacluster option being set. > > > > Did it make any performance difference? iirc the buffer_boundary stuff was > worth around 10% on a single linear read of a large, well-laid-out file. >